TB-500 is a synthetic peptide fragment of Thymosin Beta-4 (Tβ4), corresponding to the actin-binding domain of the full protein. Tβ4 is naturally expressed at high levels in platelets, wound fluid, and tissues undergoing repair. TB-500 is studied for its ability to promote cell migration and proliferation, stimulate angiogenesis, reduce inflammation, and accelerate healing across a variety of tissue types including muscle, tendon, ligament, and cardiac tissue. Research has also documented systemic distribution from local injection sites, suggesting potential for remote tissue effects. It is frequently combined with BPC-157 for a complementary approach to tissue repair research.